From f065957062095f1b563d91b8950ee7411055025c Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Thu, 30 Sep 2004 00:24:27 +0000 Subject: [PATCH] Come to think of it, functions in FROM have the same syntactic restriction as CREATE INDEX did, and can be fixed the same way, for another small improvement in usability and reduction in grammar size. --- src/backend/parser/gram.y | 55 ++++++++----------------------- src/backend/parser/parse_clause.c | 14 +++++--- src/backend/parser/parse_target.c | 5 ++- src/include/parser/parse_target.h | 3 +- 4 files changed, 26 insertions(+), 51 deletions(-) diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y index c54197ffb7..8f1b393d29 100644 --- a/src/backend/parser/gram.y +++ b/src/backend/parser/gram.y @@ -11,7 +11,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.476 2004/09/29 23:39:20 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.477 2004/09/30 00:24:20 tgl Exp $ * * HISTORY * AUTHOR DATE MAJOR EVENT @@ -5368,24 +5368,7 @@ relation_expr: ; -func_table: func_name '(' ')' - { - FuncCall *n = makeNode(FuncCall); - n->funcname = $1; - n->args = NIL; - n->agg_star = FALSE; - n->agg_distinct = FALSE; - $$ = (Node *)n; - } - | func_name '(' expr_list ')' - { - FuncCall *n = makeNode(FuncCall); - n->funcname = $1; - n->args = $3; - n->agg_star = FALSE; - n->agg_distinct = FALSE; - $$ = (Node *)n; - } +func_table: func_expr { $$ = $1; } ; @@ -6978,6 +6961,16 @@ func_expr: func_name '(' ')' n->agg_distinct = FALSE; $$ = (Node *)n; } + | NULLIF '(' a_expr ',' a_expr ')' + { + $$ = (Node *) makeSimpleA_Expr(AEXPR_NULLIF, "=", $3, $5); + } + | COALESCE '(' expr_list ')' + { + CoalesceExpr *c = makeNode(CoalesceExpr); + c->args = $3; + $$ = (Node *)c; + } ; /* @@ -7206,24 +7199,12 @@ in_expr: select_with_parens | '(' expr_list ')' { $$ = (Node *)$2; } ; -/* Case clause +/* * Define SQL92-style case clause. - * Allow all four forms described in the standard: * - Full specification * CASE WHEN a = b THEN c ... ELSE d END * - Implicit argument * CASE a WHEN b THEN c ... ELSE d END - * - Conditional NULL - * NULLIF(x,y) - * same as CASE WHEN x = y THEN NULL ELSE x END - * - Conditional substitution from list, use first non-null argument - * COALESCE(a,b,...) - * same as CASE WHEN a IS NOT NULL THEN a WHEN b IS NOT NULL THEN b ... END - * - thomas 1998-11-09 - * - * NULLIF and COALESCE have become first class nodes to - * prevent double evaluation of arguments. - * - Kris Jurka 2003-02-11 */ case_expr: CASE case_arg when_clause_list case_default END_P { @@ -7234,16 +7215,6 @@ case_expr: CASE case_arg when_clause_list case_default END_P c->defresult = (Expr *) $4; $$ = (Node *)c; } - | NULLIF '(' a_expr ',' a_expr ')' - { - $$ = (Node *) makeSimpleA_Expr(AEXPR_NULLIF, "=", $3, $5); - } - | COALESCE '(' expr_list ')' - { - CoalesceExpr *c = makeNode(CoalesceExpr); - c->args = $3; - $$ = (Node *)c; - } ; when_clause_list: diff --git a/src/backend/parser/parse_clause.c b/src/backend/parser/parse_clause.c index a0dd961363..af3cbffa70 100644 --- a/src/backend/parser/parse_clause.c +++ b/src/backend/parser/parse_clause.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/parser/parse_clause.c,v 1.136 2004/08/29 05:06:44 momjian Exp $ + * $PostgreSQL: pgsql/src/backend/parser/parse_clause.c,v 1.137 2004/09/30 00:24:21 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -497,12 +497,16 @@ transformRangeFunction(ParseState *pstate, RangeFunction *r) RangeTblEntry *rte; RangeTblRef *rtr; - /* Get function name for possible use as alias */ - Assert(IsA(r->funccallnode, FuncCall)); - funcname = strVal(llast(((FuncCall *) r->funccallnode)->funcname)); + /* + * Get function name for possible use as alias. We use the same + * transformation rules as for a SELECT output expression. For a + * FuncCall node, the result will be the function name, but it is + * possible for the grammar to hand back other node types. + */ + funcname = FigureColname(r->funccallnode); /* - * Transform the raw FuncCall node. + * Transform the raw expression. */ funcexpr = transformExpr(pstate, r->funccallnode); diff --git a/src/backend/parser/parse_target.c b/src/backend/parser/parse_target.c index 35375c39ac..b130a842af 100644 --- a/src/backend/parser/parse_target.c +++ b/src/backend/parser/parse_target.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/parser/parse_target.c,v 1.125 2004/08/29 05:06:44 momjian Exp $ + * $PostgreSQL: pgsql/src/backend/parser/parse_target.c,v 1.126 2004/09/30 00:24:21 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -41,7 +41,6 @@ static Node *transformAssignmentIndirection(ParseState *pstate, static List *ExpandColumnRefStar(ParseState *pstate, ColumnRef *cref); static List *ExpandAllTables(ParseState *pstate); static List *ExpandIndirectionStar(ParseState *pstate, A_Indirection *ind); -static char *FigureColname(Node *node); static int FigureColnameInternal(Node *node, char **name); @@ -893,7 +892,7 @@ ExpandIndirectionStar(ParseState *pstate, A_Indirection *ind) * Note that the argument is the *untransformed* parse tree for the target * item. This is a shade easier to work with than the transformed tree. */ -static char * +char * FigureColname(Node *node) { char *name = NULL; diff --git a/src/include/parser/parse_target.h b/src/include/parser/parse_target.h index e1cd2dcca5..71dfd35c1d 100644 --- a/src/include/parser/parse_target.h +++ b/src/include/parser/parse_target.h @@ -7,7 +7,7 @@ * Portions Copyright (c) 1996-2004, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * - * $PostgreSQL: pgsql/src/include/parser/parse_target.h,v 1.33 2004/08/29 04:13:09 momjian Exp $ + * $PostgreSQL: pgsql/src/include/parser/parse_target.h,v 1.34 2004/09/30 00:24:27 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -27,5 +27,6 @@ extern void updateTargetListEntry(ParseState *pstate, TargetEntry *tle, List *indirection); extern List *checkInsertTargets(ParseState *pstate, List *cols, List **attrnos); +extern char *FigureColname(Node *node); #endif /* PARSE_TARGET_H */